End-To-End-Encryption is nothing new. With messengers like Whatsapp or Telegram it's again an issue. If E2E-Encryption means that nobody but the endpoints are able to encrypt the messages, then how is this feature implemented so seamlessly?

Perf is a profiler tool for Linux 2.6+ based systems that abstracts away CPU hardware differences in Linux performance measurements and presents a simple commandline interface. Perf is based on the perf_events interface exported by recent versions of the Linux kernel. This article demonstrates the perf tool through example runs.